FEAT: Replace `load/all with `lexer/process for Red/System

Now the Red lexer support Red/System, so comment some unsuitable tests.
FIX: no need to convert "%" to "///" in R/S loader
FIX: Throw an error when convert bignumber to integer.
Merge pull request #761 from qtxie/replace-rs-load

FEAT: Replace `load/all with `lexer/process for Red/System